Depends on the route. The last time I flew Alaska to SEA was on a 737-400 a couple years ago. They've since been retired, but their current interiors are rather sterile and have those awful slimline seats. Meanwhile I think Delta will be bringing the A220 to Seattle.
Delta also flies a lot of regional carriers to SEA (and both Compass and SkyWest are pretty mediocre out of SEA). I'll take the 2x2 seating of a CRJ/ERJ over a 737 (or the Dash-8s) any day, especially Delta's newer low density layout. The Dash 8 isn't bad for a turboprop, but it's still a turboprop.
Delta also flies a lot of regional carriers to SEA (and both Compass and SkyWest are pretty mediocre out of SEA). I'll take the 2x2 seating of a CRJ/ERJ over a 737 (or the Dash-8s) any day, especially Delta's newer low density layout. The Dash 8 isn't bad for a turboprop, but it's still a turboprop.